Personal watercraft (PWCs) are typically powered by a two or four stroke internal combustion engine that is connected via a driveshaft to a jet pump. While such engines provide ample power for PWCs, they create both noise and emissions that can be undesirable. For example, many bodies of water include designated “no wake zones” along shores, docks, and/or harbors in which watercraft must maintain a reduced speed. The goal of such zones is to, among other things, limit the amount of noise and emissions created in these zones. When PWCs are operated at low speeds in locations such as these, it is where preventing noise and environmental pollution is a high priority. Farther away from docks, people, and shore, riders tend to drive PWCs faster and increased power is highly desirable.
A desire has therefore developed for a watercraft that can alternately operate at low speeds while minimizing noise and environmental pollution and at higher speeds where increased power is desired.
In the field of land-driven wheeled vehicles such as automobiles, one way environmental and noise concerns have been addressed is to provide a hybrid vehicle that simultaneously and/or alternatively uses an engine and one or more electric motors to power the vehicle.
U.S. Pat. No. 6,857,918, issued Feb. 22, 2015, the entirety of which is incorporated herein by reference, describes various embodiments of hybrid propulsion systems for a watercraft.
Many of these hybrid propulsion systems use a clutch to control the transfer of torque from the internal combustion engine and the electric motor to the jet pump. Some clutches need to be lubricated in order to operate properly. Although it is possible to provide a dedicated lubrication system to lubricate the clutch, doing so requires a lot of additional parts (pump, connection lines, lubricant reservoir . . . ) that can increase the cost of the watercraft, the complexity of assembly, and take up room in the watercraft.
There is therefore a need for a system for lubricating a clutch in a watercraft having a hybrid propulsion system.
It is also desirable to provide a conversion system that allows the conversion of a watercraft having only an internal combustion engine to have a hybrid propulsion system.